调整井防窜水泥浆体系研究

Antichannelling cement slurry system for adjustment well

孙清华 彭明旺 夏宏南 张俊 屈胜元 严维锋

长江大学石油工程学院，湖北 荆州 434023

(School of Petroleum Engineering, Yangtze University, Jingzhou 434023, China),

一些老油田经过长期的分层布井、三次加密钻井、高压注水和大排量强抽，形成了地下高压层、常压层、低压层共存的多压力体系，同时层间压差大，产层水淹严重，给固井质量带来了严重影响，一次合格率逐年下降，固井质量差已成为影响油田开发和钻井的严重技术难题。而油气水窜在调整井固井中显得尤为突出，提高固井质量已成为油田开发和钻井亟待解决的问题。文中进行了膨胀水泥浆的特性分析、防窜性能测试和沉降稳定性试验，通过评价、筛选外加剂，优选出一套能提高调整井固井质量、满足固井要求的失水量超低、防窜稳定性好的水泥浆体系。

The multiple pressure regimes, of which the underground high pressure zone, normal pressure zone and weak zone coexisted together, had been generated in some maturing fields through the layering well spacing, thrice infill drilling, high pressure water injection and powerful drawing of great delivery capacity for a long time. Meanwhile, the big intrabed pressure difference and the serious waterflooding of producing pay severely affected the cement job quality. Therefore, the once qualified rate of cement job quality is getting poor and poor year by year. The bad cement job quality had become a serious problem and prominent technique puzzler that affected the oilfield development and drilling job. However, the oil, gas and water channeling became the most prominent problem during the well cementing of adjustment well. The problem to be urgently solved now is the improvement of well cementation quality for exploitation and drilling. This article conducts the property analysis of expanding cement slurry, the property test of antichannelling cement scurry and the stability test of cement slurry subsidence. We have optimized a set of cement slurry system that can improve the well cementation quality and can meet the well cementing requirement through the evaluation and selection of additives. The cement slurry system has the property of ultra-low dehydration and good antichannelling stability.